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61.
Cristin J. Monaco Corey J. A. Bradshaw David J. Booth Bronwyn M. Gillanders David S. Schoeman Ivan Nagelkerken 《Global Change Biology》2020,26(10):5564-5573
Climate change is redistributing marine and terrestrial species globally. Life‐history traits mediate the ability of species to cope with novel environmental conditions, and can be used to gauge the potential redistribution of taxa facing the challenges of a changing climate. However, it is unclear whether the same traits are important across different stages of range shifts (arrival, population increase, persistence). To test which life‐history traits most mediate the process of range extension, we used a 16‐year dataset of 35 range‐extending coral‐reef fish species and quantified the importance of various traits on the arrival time (earliness) and degree of persistence (prevalence and patchiness) at higher latitudes. We show that traits predisposing species to shift their range more rapidly (large body size, broad latitudinal range, long dispersal duration) did not drive the early stages of redistribution. Instead, we found that as diet breadth increased, the initial arrival and establishment (prevalence and patchiness) of climate migrant species in temperate locations occurred earlier. While the initial incursion of range‐shifting species depends on traits associated with dispersal potential, subsequent establishment hinges more on a species’ ability to exploit novel food resources locally. These results highlight that generalist species that can best adapt to novel food sources might be most successful in a future ocean. 相似文献
62.
Csilla Stenger‐Kovcs Edina Lengyel Krisztina Buczk Judit Padisk Jnos Korponai 《Ecology and evolution》2020,10(1):320-335
Saline lakes, among the most seriously endangered ecosystems, are threatened due to climate change and human activities. One valuable feature of these environments is that they constitute areas of high biodiversity. Ecologists are, therefore, under great pressure to improve their understanding of the effects of natural and anthropogenic disturbances on the biodiversity of saline lakes. In this study, a total of 257 samples from 32 soda pans in Central Europe between 2006 and 2015 were examined. The effects of environmental variables and of geographical and limnoecological factors on functional diversity were analyzed. Furthermore, the explanatory power of the trait‐based approach was assessed, and the applicability of the indices for biomonitoring purposes was determined. It was found that low habitat heterogeneity and harsh environments lead to the selection of a small number of suitable traits, and consequently, to a naturally low level of functional diversity. Anthropogenic activities enhance diversity at functional level due to the shift toward freshwater characteristics. On the regional scale, the effects of the region and status (natural, degraded, reconstructed) on diatom functional diversity were significant and more pronounced than that of the environmental and other limnoecological factors. The degree of variance found in functional diversity ascribed to environmental variables is five times greater in the case of the application of a trait‐based approach, than when a taxonomic one is employed in the literature. Each of the tested functional diversity indices was sensitive to the most important environmental variables. Furthermore, these were type‐specific and proved to be more complex indicators than taxonomic metrics. It is possible to suggest four functional diversity indices (FGR, FRic, FDis, and FDiv) which emphasize their independence from substrate and seasonal variations for ecological status assessment and conservation planning. 相似文献
63.
Gregory M. Crutsinger Seth M. Rudman Mariano A. Rodriguez‐Cabal Athena D. McKown Takuya Sato Andrew M. MacDonald Julian Heavyside Armando Geraldes Edmund M. Hart Carri J. LeRoy Rana W. El‐Sabaawi 《Molecular ecology》2014,23(23):5888-5903
A ‘genes‐to‐ecosystems’ approach has been proposed as a novel avenue for integrating the consequences of intraspecific genetic variation with the underlying genetic architecture of a species to shed light on the relationships among hierarchies of ecological organization (genes → individuals → communities → ecosystems). However, attempts to identify genes with major effect on the structure of communities and/or ecosystem processes have been limited and a comprehensive test of this approach has yet to emerge. Here, we present an interdisciplinary field study that integrated a common garden containing different genotypes of a dominant, riparian tree, Populus trichocarpa, and aquatic mesocosms to determine how intraspecific variation in leaf litter alters both terrestrial and aquatic communities and ecosystem functioning. Moreover, we incorporate data from extensive trait screening and genome‐wide association studies estimating the heritability and genes associated with litter characteristics. We found that tree genotypes varied considerably in the quality and production of leaf litter, which contributed to variation in phytoplankton abundances, as well as nutrient dynamics and light availability in aquatic mesocosms. These ‘after‐life’ effects of litter from different genotypes were comparable to the responses of terrestrial communities associated with the living foliage. We found that multiple litter traits corresponding with aquatic community and ecosystem responses differed in their heritability. Moreover, the underlying genetic architecture of these traits was complex, and many genes contributed only a small proportion to phenotypic variation. Our results provide further evidence that genetic variation is a key component of aquatic–terrestrial linkages, but challenge the ability to predict community or ecosystem responses based on the actions of one or a few genes. 相似文献
64.
Pirkko Kortelainen Tuula Larmola Miitta Rantakari Sari Juutinen Jukka Alm Pertti J. Martikainen 《Global Change Biology》2020,26(3):1432-1445
Estimates of regional and global freshwater N2O emissions have remained inaccurate due to scarce data and complexity of the multiple processes driving N2O fluxes the focus predominantly being on summer time measurements from emission hot spots, agricultural streams. Here, we present four‐season data of N2O concentrations in the water columns of randomly selected boreal lakes covering a large variation in latitude, lake type, area, depth, water chemistry, and land use cover. Nitrate was the key driver for N2O dynamics, explaining as much as 78% of the variation of the seasonal mean N2O concentrations across all lakes. Nitrate concentrations varied among seasons being highest in winter and lowest in summer. Of the surface water samples, 71% were oversaturated with N2O relative to the atmosphere. Largest oversaturation was measured in winter and lowest in summer stressing the importance to include full year N2O measurements in annual emission estimates. Including winter data resulted in fourfold annual N2O emission estimates compared to summer only measurements. Nutrient‐rich calcareous and large humic lakes had the highest annual N2O emissions. Our emission estimates for Finnish and boreal lakes are 0.6 and 29 Gg N2O‐N/year, respectively. The global warming potential of N2O from lakes cannot be neglected in the boreal landscape, being 35% of that of diffusive CH4 emission in Finnish lakes. 相似文献
65.
In the Mediterranean region, wildfires have devastating effects on animals with limited mobility. With their poor dispersal
abilities, their habitats on vegetation and in litter, and their sensitivity to humidity and shade, we expected land snails
to be an interesting model to assess short, medium and long-term impact of fires on fauna biodiversity and their resilience.
Stratified sampling was carried out on 12 sampling sites in garrigues and forests of Provence (southeastern France), according
to fire regime (number of fires, fire intervals and age of the last fire) over the past 30 years. Data were investigated using
diversity indexes, Kruskal–Wallis test, dendrogram of affinities and Correspondence Analysis (CA). We found, however, that
Mediterranean land snail communities are particularly resilient to fires. Although abundance is drastically reduced in the
short-term, species richness and community diversity are preserved provided that the time lapse between two successive fires
is longer than the time required for recovery (i.e. around 5 years). This high community resilience in the short-term may
be partly due to ecological and ethological aptitudes of land snails. However, these astonishing results, which have implications
for conservation biology, are mainly due to the presence, within burned areas, of cryptic refuges that allow initial land
snail survival, malacofauna persistence after successive fires and consistent biogeographical patterns in the long-term. 相似文献
66.
Analysis of nitrogen saturation potential in Rocky Mountain tundra and forest: implications for aquatic systems 总被引:2,自引:1,他引:2
Jill S. Baron Dennis S. Ojima Elisabeth A. Holland William J. Parton 《Biogeochemistry》1994,27(1):61-82
We employed grass and forest versions of the CENTURY model under a range of N deposition values (0.02–1.60 g N m–2 y–1) to explore the possibility that high observed lake and stream N was due to terrestrial N saturation of alpine tundra and subalpine forest in Loch Vale Watershed, Rocky Mountain National Park, Colorado. Model results suggest that N is limiting to subalpine forest productivity, but that excess leachate from alpine tundra is sufficient to account for the current observed stream N. Tundra leachate, combined with N leached from exposed rock surfaces, produce high N loads in aquatic ecosystems above treeline in the Colorado Front Range. A combination of terrestrial leaching, large N inputs from snowmelt, high watershed gradients, rapid hydrologic flushing and lake turnover times, and possibly other nutrient limitations of aquatic organisms constrain high elevation lakes and streams from assimilating even small increases in atmospheric N. CENTURY model simulations further suggest that, while increased N deposition will worsen the situation, nitrogen saturation is an ongoing phenomenon. 相似文献
67.
Jean‐François Ponge 《Ecology and evolution》2013,3(4):1113-1124
The present text exposes a theory of the role of disturbances in the assemblage and evolution of species within ecosystems, based principally, but not exclusively, on terrestrial ecosystems. Two groups of organisms, doted of contrasted strategies when faced with environmental disturbances, are presented, based on the classical r‐K dichotomy, but enriched with more modern concepts from community and evolutionary ecology. Both groups participate in the assembly of known animal, plant, and microbial communities, but with different requirements about environmental fluctuations. The so‐called “civilized” organisms are doted with efficient anticipatory mechanisms, allowing them to optimize from an energetic point of view their performances in a predictable environment (stable or fluctuating cyclically at the scale of life expectancy), and they developed advanced specializations in the course of evolutionary time. On the opposite side, the so‐called “barbarians” are weakly efficient in a stable environment because they waste energy for foraging, growth, and reproduction, but they are well adapted to unpredictably changing conditions, in particular during major ecological crises. Both groups of organisms succeed or alternate each other in the course of spontaneous or geared successional processes, as well as in the course of evolution. The balance of “barbarians” against “civilized” strategies within communities is predicted to shift in favor of the first type under present‐day anthropic pressure, exemplified among others by climate warming, land use change, pollution, and biological invasions. 相似文献
68.
69.
70.
Rodolfo A. Golluscio Amy T. Austin Guillermo C. García Martínez Marina Gonzalez-Polo Osvaldo E. Sala Robert B. Jackson 《Ecosystems》2009,12(4):686-697
We explored the net effects of grazing on soil C and N pools in a Patagonian shrub–grass steppe (temperate South America).
Net effects result from the combination of direct impacts of grazing on biogeochemical characteristics of microsites with
indirect effects on relative cover of vegetated and unvegetated microsites. Within five independent areas, we sampled surface
soils in sites subjected to three grazing intensities: (1) ungrazed sites inside grazing exclosures, (2) moderately grazed
sites adjacent to them, and (3) intensely grazed sites within the same paddock. Grazing significantly reduced soil C and N
pools, although this pattern was clearest in intensely grazed sites. This net effect was due to the combination of a direct
reduction of soil N content in bare soil patches, and indirect effects mediated by the increase of the cover of bare soil
microsites, with lower C and N content than either grass or shrub microsites. This increase in bare soil cover was accompanied
by a reduction in cover of preferred grass species and standing dead material. Finally, stable isotope signatures varied significantly
among grazed and ungrazed sites, with δ15N and δ13C significantly depleted in intensely grazed sites, suggesting reduced mineralization with increased grazing intensity. In
the Patagonian steppe, grazing appears to exert a negative effect on soil C and N cycles; sound management practices must
incorporate the importance of species shifts within life form, and the critical role of standing dead material in maintaining
soil C and N stocks and biogeochemical processes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Author Contributions RAG designed study, performed research, analyzed data, wrote the paper; ATA designed study, wrote the paper; CGGM designed
study, performed research, analyzed data; MGP performed research; OES designed study; RBJ designed study, contributed new
methods. 相似文献